Objective: To estimate the total antioxidant status (TAS), level of Glutathione (GSH) and Malondialdehyde (MDA) in blood plasma of bipolar disorder (BD) patients and to compare them with those in healthy controls. Materials and Methods: The levels were estimated in 154 bipolar disorder individuals and 154 age and sex matched controls without a family history of BD. All the patients included in the present study belonged to North Coastal Andhra Pradesh. Student t test was used for comparison. Results: Mean blood plasma levels of TAS and GSH were significantly lower (p=<0.05) while the level of MDA (p=0.06) was higher in cases compared to controls. Gender wise analysis revealed that TAS and GSH were significantly (p= 0.05) associated with BD in both the sexes. Conclusion: A significant decrease in the level of TAS and GSH and increase of MDA in BD cases suggest the probable role of oxidative stress in the pathogenesis of BD.